Magnetic chuck



1960 w. MOUER ET AL 2,922,933

MAGNETIC CHUCK Filed May 31, 1955 2 Sheets-Sheet 1 ./0 il H ,6 6mm. 22 9 I r /5 20 20 /7 7 23 FIG.

l5 /9 20 /7 Q0 /8 23 A? Q l0 f /6 a --23 Ha M 28 5 /2 a0 28 27 M W a *7.

IN VENTOR 5 BY%4M, M,

ATTORNEYS Jan. 26, 1960 QUER Em 2,922,933 MAGNETIC 2,922,933 MAGNETIC CHUCK Earl W. Muller and Glenn M. Snyder, Waynesboro, Pa., assignors to Landis Tool Company, Waynesboro, Pa.

Application May 31, 1955, Serial No. 512,259, 7 Claims. (Cl. 317-159) The invention to which the following specification relates is that of a replacement or renewal, i.e. recharging.

Another object is to make the magnets removable with maximum ease.

By way of example the preferred form of the invention has been illustrated on the accompanying drawings in which: 1

Figure 1 is a front elevation-a1 view of the improved magnetic chuck;

Figure 2 is a 2-2 of Figure 1;

Figure 3 is a Figurev2, and

Figure 4 is a similar section on the line 4-4 of Figure 2. r V

Briefly, stated, the invention consists in providing a body member in which fixed pole pieces are imbedded in the face for holding the work piece. At the same time use is made of a series of bar magnets arranged in parallel spaced formation in contact with the underside of said pole pieces. Finally, the rear ends of the bar magnets are in contact longitudinal vertical section on the line transverse section on the line 3-3 of cent pairs of magnet poles. v

In the drawings, a rotary headstock 6 has been shown as the base upon which the magnetic chuck is mounted. This headstock carries a removable face plate 7. Both the headstock and the face plate are of well known constniction.

The magnetic chuck consists essentially of a shell or body member 8. This is made ofnon-magnetic material to which the pole pieces are brazed. The body member 8 has a circular base 9 proportioned to fit upon the face 2,922,933 Patented Jan. 26, 1960 plate 7 and to be removably attached thereto by means of bolts 10, 10.

The body member has a series of cylindrical chambers pole.

A corresponding number of individual pole pieces 15, 16, 17 and 18 are imbedded in the front face of the memproper.

Bar magnets 24, 25, 26 and 27 fit within the chambers 11, 12, 13 and that they are not held by friction.

just loosely enough 14 respectively, so

A threaded 29 is provided for a purpose which will be described later.

A magnetic chuck constructed as above described is easily mounted on a headstock or the like without modification of the latter. A permanent The magnets are inserted with reverse direction of the poles so that alternate adjacent pole pieces are negative and positive respectively.

The common armature 29 closes in the rear ends of of sufiiciently greater mass than the pole pieces 15, 16, 17, and 18 that the attraction between the armature and the magnets is greater than between the pole pieces and when the armature 29 is removed, the attraction between the magnets and the pole pieces is broken and the magnets are removed with the armature.

The path of magnetic passes from the front end of one magnetand'its pole piece to the workpiece. The flux returns from the workpiece to the adjacent pole piece and the magnet. The path is closed ,by that part of the armature or disk 29 which bridges the rear ends of the magnets being considered. a

While the invention has been described in'its preferred form, it will "be well understood that minor changes of proportions, arrangement and materials are possible without departing from the'scope of the invention as defined in the following claims.

What is claimed is:

1. A magnetic chuck comprising a non magnetic body member having'a base removably attachable to a headstock, said body member-having a series of circumferentially spaced longitudinal chambers extending therethrough, a radial pole piece imbedded in the front of the body member over each chamber and individually spaced apart, a permanent bar magnet removably carried in each chamber with their front ends in contact with the respective pole pieces and said ends arranged with alternate polarity, and an armature removably held in the base against the rear ends of the magnets.

2. A magnetic chuck comprising a non-magnetic'body member havingya base removably attachable to a headstock, said body member having a series of circumferentially spacedlongitudinal chambers extending therethrough, a radial pole piece imbedded in the front of the body member over each chamber and individually spaced apart, each pole piece having a non-magnetic radial wearresistant bar flush with the surface of said pole piece, a permanent bar magnet removably carried in each chamber with their front ends in contact with the respective pole pieces and said ends arranged with alternate polar ity, and an armature removably held in the base against the rear ends of the magnets. a

3. A magnetic chuck comprising a non-magnetic body member having a base removably attachable to a headstock, said body member having'a series of circumferentially spaced longitudinal chambers extending therethrough, a radial pole piece imbedded in the front of the body member over each chamber, said pole pieces having pointed inner endslying in spaced juxtaposition and extending toward the center of the chuck, and a permanent bar magnet removably carried in each chamber with its front end in contact with one of said pole pieces and said front ends of the magnets arranged with alternate polarity, and an armature removably held in the base against the rear ends of the magnets.

4. A magnetic chuck comprising a non-magnetic body member having a base removably attachable to a headstock, said body member having a series of circumferentially spaced longitudinal chambers extending therethrough, a radial pole piece imbedded in the front of the body member over each chamber, each pole piece having a pointed inner-end, non-magnetic spacers between said inner ends, a permanent bar magnet removably carried in each chamber with their front ends in contact with the respective pole pieces and said ends arranged with alternate polarity, and an armature removably held in the base against the rear ends of the magnets.

5. A magnetic chuck comprising a non-magnetic body member having a base removably attachable to a headstock, said body member having a series of circumferentially spaced longitudinal chambers extending therethrough, a radial pole piece imbedded in the front of the body member over e ch ehamber and individually spaced apart, a permanent bar magnet removably carried in each'chamber with their front ends in contact with the respective pole pieces and saidends arranged with alternate polarity, l removably held in magnets.

A n i u k gmn sisg a rp -ma neti o member having abasle removbly attachable to ahead stock, said body me her having a series of circumferentially spaced longit 'hambersextending there through, a counterbored cavity the base of the member overlying the rear ends of the chambers, a radial pole piece imbedded in the front 9f the body member over each chamber, a permanent magnet removablyoarand a magnetically permeable disk the base against the rear ends of the ried in each chamber with their front ends in contact with the respective pole pieces and said ends arranged with alternate polarity, and an armature disk removably held in said counterbored cavity in contact with the rear ends of said magnets. v

7. A magnetic chuck comprising a non-magnetic body member having a base removably attachable to a headstock, said body member having a series of circumferr entially spaced longitudinal chambers extending therethrough, a radial pole piece imbeddd'in the front of the body member over each chamber and individually spaced apart, a permanent bar ma net removably carried in each chamber with their front ends in contact with the respective pole pieces and said ends arranged with alternate polarity, and an armature disk removably held in the base against the inner ends of the magnets, the magnetic attractionbetween said annature and the combined magnets being sufiicient on removal of the armature to separate said magnets from the individual pole pieces and to withdraw said magnets from the chambers.

r n e 9W h 1169? th s a UNITED STATES PATENTS 974,760 Eastwood Nov. 1, 1910 1,484,090 1 Simmons Feb. 19, 1924 2,179,625 Groden Nov. 14, 1939 2,287,286 Bing et al June 23, 1942 2,479,584- Meyer Aug. 23, 1949 2,778,669 Goodwin Ian. 22, 1957 FOREIGN PATENTS 700,352 Germany 1-8, 1940 

